Pneumatic-despatch apparatus.



PATENTED OCT. 27, 1903.

, G. P. STO EDARD. PNEUMATIC DESPATGH APPARATUS.

APPLICATION FILED MAR 1,. 1.903;

N0 MODEL.

' v INVENTOR. M 7

WITNESSES.-

Afro/mini.

UNITED STATES Patented October 27, 190E").

PATENT OFFICE.

CHARLES F. STODDARD, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO AMERIOAN'PNEUMATIO SERVICE COMPANY, OF DOVER, DELAWARE,

A CORPORATION OF DELAWARE.

MATlC-'DESPATCH APPARATUS.

SPECIFICATION forming part of Letters Patent No. Mama-dated October 27, 1903.

' Application filed March 6, 190a. SerialNo. 146,556, (No model.)

1'0 aZZ whom it may concern:

Be it known that I, GHARLnsF. STODDARD, of Boston, in the county of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Pneumatic-Despatch Apparatus, of which the following isa specification.

My invention relates to improvements in pneumatic despatch apparatus, and espe' cially to a terminal which receives the carrier at the end of the transmission-tube. l

The object of my invention is to simplify the operation and the parts.

In my apparatus there is a transmission- I tube in connection with a receiving-chamber having an opening on the lower side large enough to admit of a carrier dropping out. The portion of the chamber over said opening is bent in such a curve as to hold a'carrier to the top of the chamber by centrifugal force as the carrier is coming in. The part of the receiving-chamber above the opening is arranged so that the carrier will come to a stop by cushioning on the air and by so cushioning will open a valve in a pipe'supplying air under pressure to the cushioning-chamber at its extreme upper end. This air under pressure is admitted to the cushioning-chamber in front of the carrier in order to bring it to a stop quickly and then force it out of the chamber quickly. A means is provided for closing the valve after the carrier has left the chamber through the opening. A buffer is arranged to stop the carrier as it leaves the chamber, and a table is provided for the carrier to fall onto. Because of the high speed of the carrier as it passes the opening coming in it is held to the top of the chamber by the centrifugal force thus generated; but in the discharging operation the carrier is moving at a greatly-decreased speed, which does not generate any appreciable centrifugal force. Therefore the carrier drops onto the buffer instead of falling into the lower portion of the receiving-chamber and sliding back-into the transmission-tube. A slotted casin g is interposed between the transmission-tube and the receiving-chamber, to which is attached a pipe. Through this pipe the air from thetransmission-tube is drawn away, so that it does not flow'out of the opening in the receiving-chamber.

My invention consists of certain novel features hereinafter described, and particularly pointed out in the claims.

In the accompanying drawings, which illustrate a construction embodying myinvention, Figure 1 is a side elevation of the complete machine. Fig. 2 is a sectional view through the upper part of the machine, showing the valve mechanism.

Like letters of reference refer to like parts throughout both views.

The transmission-tube A is in communica ,tion with the discharge-tube B through the slotted casing D, which is provided with openings D. To this'slotted casing is attached the receiving-terminal O, which is bent at C, so as to hold the carrier to the upper side as it passes the opening 0 before entering the compression-chamber O E is a buifer for the purpose of checking the carrier as it comes out of the compressionchamber 0 and E is a table for receiving the carrier, which table is secured to the rings E 'E G is a supply-pipe for air under pressure, and G is a check-valve in the valve-casing G for preventing the cushion-pressure escaping into the pipe Or should it be greater than the pressure of air in the pipe G. The short piece of pipe G is to strengthen the support of the tube O and is not used to conduct air,

.being stopped off at its lower end.

L is a valve in the valve-casing G which prevents the air under pressure in the pipe G from escaping into the atmosphere through the compression-chamber 0 when the machine is in its normal position.

K is a flexible diaphragm inclosed in the diaphragm-casings K K To this diaphragm is securely fastened'the piston-rodL, which in turn is secured to the valve L. The chamber between the diaphragm K and the casing K is in communication with the compressionohamber 0 through the pipe H. The plates K K are for the purpose of stiffening the diaphragm at the center, so that the working area of the diaphragm is made greater. The spring J holds the valve L normally against ICO its seat. The compression chamber 0 is stopped oif at its upper end by the plug F, to one side of which is fastened the safetybuifer F.

E E are supports for the table E, and E supports the bufier E.

B is a pipe through which air from the transmission-tube A is carried to the com pressors.

a a represent the floor-line.

The operation is as follows: The carrier comes in through the transmission-tube A and passes through the slotted casing D into the receiving-terminal 0. Above the opening 0 near the center of the receiving-terminal the tube 0 of the terminal is bent to such a radius as to hold the carrier to the upper side as it passes the opening 0 the speed and weight of the carrier determining the amount of centrifugal force, which in turn determines the necessary radius of the curve. The carrier entering the compression-chamber O raises the air therein to a higher pressure than the atmosphere and communicates this pressure to the diaphragm K through the tube H, which connects with the compressionchamber at H, a point below the buffer F. When the pressure forces the diaphragm K away from the casing K, the valve L is raised from its seat. As a tight-fitting carrier will raise the pressure of the air in the chamber 0 higher than a loose-fitting carrier, there is provided a check-valve G so that the pressure in the chamber C" will be raised higher than the pressure of the air in the pipe G and the cushion-pressure in the chamber C will not spill into the pipe G; but if the carrier is loose-fitting and does not raise the pressure in the chamber 0 as high as the pressure in the pipe G when it cushions the air in the pipe G will rush into the chamber 0 and assist in raising the pressure of the cushion in the chamber 0 so as to bring the carrier to a stop quickly. The cushion-pressure in the chamber C is sufiicient, however, to open the valve L, so that the pressure in the pipe G can pass into the cushion-chamber (J Now so long as the carrier remains in the chamber C it holds the pressure in front of it, which pressure in turn holds the diaphragm K away from the casing K, thereby keeping the valve L open. This pressure forces the carrier back to the opening 0 but under much less speed, on account of the area of the pipe G, than when it passes the opening in coming in, so that there is not enough centrifugal force in the carrier to hold it against the upper part of the tube. It therefore drops as it comes into the opening 0 against the butter E and is received upon the table E. This leaves the chamber 0 open to the atmosphere, which in turn leaves the chamber between the diaphragm K and the casing K open to the atmospheric pressure, which allows the spring J to force the valve L back to its seat, which shuts 011' the How of air from the supply-pipe G. The air is drawn ofi from the transmission-tube A through the openings D in the slotted casing and through the pipe B.

Having thus described the nature of my invention and set fortha construction embodying the same, what I claim as new, and desire to secure by Letters Patent of the United States, is-

1. In a pneumatic-despatch apparatus, a transmission-tube for the carriers, a receivingterminal in communication with said transmission-tube provided with a side opening for the delivery of the carriers and with the tube curved opposite said opening so as to hold the carriers against said curve by contrifugal force, a cushioning-chamber beyond said opening for stopping the carrier by compressing the air in its travel and from which the carrier returns and passes out of said side opening.

2. In a pneumatic -despatch apparatus, a transmission-tube for the carriers, a receiving terminal in communication with said transmission-tube provided with a side opening for the delivery of the carriers and with the tube curved opposite said opening so as to hold the carriers against said curve by centrifugal force, a cushioning-chamber beyond said opening for stopping the carrier by compressing the air in its travel and from which the carrier returns and passes out of said side opening, an air-pressure-supply pipe in communication with said cushioning-chamber, a valve normally closing said communication, mechanism for opening said valve operated by the air compressed by the carrier to permit air from the air-supply pipe to pass into said cushioning-chamber for the cushioning of the carrier when the pressure in the supplypipe is greater than that in the cushioningchamber.

3. In a pneumatic-despatch apparatus, a transmission-tube for the carriers, a receivingterminal in communication with said transmission-tube provided with a side openin g for the delivery of the carriers, a cushioning-chamber beyond said opening for stopping the carrier by compressing the air in its travel and from which the carrier returns and passes out of said side opening, an air-pres- IIO sure-supply pipe in communication with said cushioning-chamber, a valve normally closing said communication, mechanism for opening said valve operated by the air compressed by the carrier to permit air from the air-supply pipe to pass into said cushioning-chamber for the cushioning of the carrier when the pressure in the supply-pipe is greater than that in the cushioning-chamber, and a check-valve for closing communication between the cushioning-chamber and the air-pressure-supply pipe when the pressure in the cushioningchamber is greater than that in the air-pressure-supply pipe.

In a pneumatic-despatoh apparatus, a transmission-tube for the carriers, a receivingterminal in communication with said transmission-tube with a side opening for the delivery of the carriers and with the tube curved opposite said opening so as to hold the carrier against said curve by centrifugal force, a cushioning-chamber beyondsaid opening for stopping the carrier by compressing the air in its travel and from which the carrier returns and passes out of said side opening.

Intestimony whereof I have signed my 10 name to this specification in the presence of two subscribing witnesses, this 4th day of March, A. D. 1903.

CHARLES F. STODDARD.

- Witnesses:

A. L. MESSER, A. R. LARRABEE. 

